Well, you COULD, but very few companies port now due to Apple refusing to update their OpenGL drivers in favor of Metal. Nowadays it's a bit better, with MoltenVK providing Vulkan support, but you're still mostly limited to Apple Arcade games and emulators for your gaming needs

MacOS still has horrible support for wine. Linux's implementation of proton has become so good, that r/wine_gaming essentially has become nothing but MacOS helpdesk tickets now!

Yeah. There was a whale event in TF2 back when it was ported where you got Apple earbuds ingame if you played the Mac port during a certain timeframe.

Since maybe 2010? That's when I first played portal and it was on a Mac.

The thing that suprises me in the headline: You can actually run steam and games on macOS?

Steam on my Mac is merely an updater for Krita.

1. No

2. You will be unable to read bullet #1 without using Apple's undocumented, unversioned mystery Apple Silicon translator that "Just works" *

* it does not, in fact, "just work"